Such a hydraulic axial piston motor with an adjustable speed of rotation is, for example, the variable displacement motor A6VM manufactured by Mannesmann Rexroth Company. In the case of such motors owing to the provision of a hydraulic setting device arranged in the terminal plate and having a pin running in a hole in the flow control disk it is possible for the cylinder block, which is supported in a freely rotatable manner in the recess having the form of a spherical segment of the correspondingly complementary spherical segment-like inner side of the flow control disk, to be moved between its maximum pivot angle at 26.5.degree. at which the motor produces maximum torque at the minimum speed of rotation, and a pivot angle approximately equal to 0.degree.. Because on approaching a pivot angle of 0.degree. there is a reduction in torque, at a pivot angle range of generally 2.degree. to 3.degree. the motor will enter the stall range. If, however, the motor is pivoted out of the 0.degree. pivot angle range or, respectively, out of the stall range towards a larger pivot angle, it will, in the absence of any external load, quickly run up to speeds of rotation in excess of the permissible speeds after leaving the stall range. This is because at small pivot angles, the intake volume which is necessary for achieving high and impermissible speeds of rotation is relatively small.
Hydraulic variable displacement motors of the type initially mentioned are more especially utilized for multi-motor drives. Such a motor is illustrated diagrammatically in FIG. 13 of the drawings herein. In the case of this multi-motor drive, a variable displacement motor is constantly coupled via a common output shaft, whereas further variable displacement motors may be connected via couplings and suitable gearing stages, which may be even able to be connected and disconnected, in order to run through the speed of rotation-torque ranges which are optimum for given purposes of application. In the case of such drives there is the particular problem of "jerks" occurring while connecting variable displacement motors which have been uncoupled. Such jerks occur because the motor is still in its stall range, or because when the motor is supplied with hydraulic oil and is not under load, it immediately runs up to its maximum speed.